Andy Roddick became the first big-name seed to crash out of the US Open men's
singles as he lost a fifth-set tie-break to fellow American John Isner.

Big-serving Isner, at 6ft 9ins tall, was always going to be handful for the fifth seed but after Roddick's fifth-set Wimbledon final heartbreak, the momentum appeared to be with the higher-ranked player whose 2003 US Open win made him the last American man to win a grand slam.

Isner proved he was no respecter of major tournament form, though, as he blasted his way into the match to take the first two sets, and then withstood a furious comeback from Roddick before holding his nerve to take an epic deciding tie-break.

Isner won 7-6 (7-3), 6-3, 3-6, 5-7, 7-6 (7-5) in three hours and 51 minutes at Arthur Ashe Stadium and will now play 10th seed Fernando Verdasco of Spain in the fourth round.

After the classic tussle between Maria Sharapova and giant-killing American teenager Melanie Oudin, Roddick and Isner continued the drama on Ashe to the delight of the day session fans given extended value for money as night fell in New York.

The opening set stayed with serve as Isner out-Roddicked Roddick with nine aces to the genuine article's four to push it into a tie-break, which the world number 55 took with some powerhouse tennis.

Roddick looked tetchy having played well in the first set but the pattern continued as Isner kept on playing out of his skin, breaking the fifth seed to take a 4-2 lead. At 5-3 he served for the second set and sealed it with an ace to take a 2-0 lead over a shell-shocked Roddick.

Isner had more than a booming serve in his locker, though, and to Roddick's frustration he was more than happy to come to the net and attempt to lob his rival at every opportunity.

Roddick, though, was edging into the ascendancy in the third set and in the eighth game he made the breakthrough.

Isner saved two break points with aces down the middle but could not stop Roddick taking the third with a great stretching backhand off the ground to pass Isner down the line.

Roddick served out to love and was back in the match at 2-1.

The fourth set was equally tight and went with serve before Isner got a sniff of a break at 5-4 up, one that would hand him the match.

Serving to stay in the match, Roddick fell to 15-30 before delivering a 132mph serve out wide for an ace. But he chose exactly the moment to deliver his first double fault of the contest, gifting Isner a match point.

Again Roddick came up trumps, with an ace down the middle to get to deuce before holding serve.

Next it was Isner's turn to feel the heat, handing over a break point with an overhead that went long, and then seeing Roddick convert, the Wimbledon finalist running back to his chair with arm raised to prepare to serve for the set at 6-5.

Isner began to shows signs of cramping as Roddick went 15-0 up, clutching his left lower leg as the fifth seed gave himself triple set point, levelling the match with an ace down the middle as the game clock edged towards three hours.

The final set went with serve, Roddick serving second and playing catch up. Both men found it easy to blast their way to victory in games, Isner taking it to extremes as he sent down a 118mph second serve ace at 4-4 before winning the game with his 36th ace of the match.

Roddick once more had to serve to stay in the match and force a deciding tie-break at 6-5 down and he came through, serving to love to send the match down to the wire.

Isner claimed the initiative to earn a mini-break off Roddick with a cross-court backhand beyond his rival's reach at the net to move 4-2 ahead.

Isner earned three match points at 6-3 but Roddick pulled out a wide ace and then saved another match point with an ace down the middle.

Back on serve, Isner sealed the biggest victory of his career when Roddick netted a forehand and the fans inside Ashe erupted in delight after another classic contest.